JP7332296B2 - Terminal, base station, wireless communication system, and preamble transmission method - Google Patents

Description

The present invention relates to user equipment and base stations in wireless communication systems.

In LTE (Long Term Evolution), random access (RA: Random Access) is performed when a user apparatus establishes a connection with a base station, resynchronizes, or the like (Non-Patent Document 1).

In addition, in 3GPP (3rd Generation Partnership Project), a wireless communication system called 5G is being developed in order to further increase the system capacity, further increase the data transmission speed, and further reduce the delay in the wireless section. is under consideration. In 5G, various radio technologies are being studied in order to meet the requirements of realizing a throughput of 10 Gbps or more and reducing the delay in the radio section to 1 ms or less. Since 5G is likely to adopt a different radio technology from LTE, 3GPP calls a radio network that supports 5G a new radio network (NewRAT: New Radio Access Network), and a radio that supports LTE. Distinguished from network. NewRAT may also be called NR.

5G is expected to use a wide range of frequencies from a low frequency band similar to that of LTE to a frequency band even higher than that of LTE. In particular, since the propagation loss increases in a high frequency band, application of beamforming with a narrow beam width is being studied in order to compensate for it.

3GPP TS 36.321 V14.0.0 (2016-09)

When a signal is transmitted by applying beamforming, the base station or the user equipment performs beam sweeping or the like to improve the reception quality of the communication partner so that the transmission beam (Tx-beam) is It is conceivable to determine the direction of Similarly, when receiving signals by applying beamforming, the base station or the user equipment can determine the direction of the reception beam (Rx-beam) so that the reception quality from the communication partner is good. Conceivable.

Here, also in NR, it is assumed that a random access procedure similar to the random access procedure in LTE is performed. However, in NR, application of beamforming as described above is also being considered in random access procedures.

However, when beamforming is applied in a random access procedure, for example, when the user equipment detects a plurality of base station side transmission beams, which resource is used to notify the base station of the RA preamble, etc. Not obvious in the prior art. Conventional techniques may not be able to properly perform random access procedures in wireless communication systems that apply beamforming.

The present invention has been made in view of the above points, and provides a technique that enables appropriate execution of a random access procedure to which beamforming is applied in a wireless communication system having a user equipment and a base station. for the purpose.

According to the disclosed technique, a receiver that receives a plurality of synchronization signal blocks corresponding to a plurality of beams;
a transmitting unit that transmits a preamble using one resource among a plurality of resources corresponding to the plurality of synchronization signal blocks;
The receiving unit receives an SIB transmitted on a beam among a plurality of SIBs transmitted on a plurality of beams, and each of the plurality of SIBs includes information on the plurality of resources.
A terminal is provided.

According to the disclosed technique, a technique is provided that enables a radio communication system having a user equipment and a base station to appropriately execute a random access procedure to which beamforming is applied.

1 is a configuration diagram of a radio communication system according to an embodiment of the present invention; FIG. FIG. 4 is a diagram for explaining an example of a random access procedure; FIG. 2 is a diagram for explaining beams transmitted from a base station 20; FIG. FIG. 4 is a diagram for explaining a method of transmitting an RA preamble; FIG. 10 is a diagram for explaining an operation example when the user device 10 can receive a plurality of broadcast information/SS; FIG. 10 is a diagram for explaining Example 1-1; FIG. 10 is a diagram for explaining Example 1-1; FIG. 10 is a diagram for explaining Example 1-2; FIG. 10 is a diagram for explaining Example 1-3; FIG. 10 is a diagram for explaining an example 1 of the RA preamble transmission method in the second embodiment; FIG. 10 is a diagram for explaining example 2 of the RA preamble transmission method in embodiment 2; FIG. 12 is a sequence diagram when the base station 20 instructs the user apparatus 10 on the RA preamble transmission method in the second embodiment; FIG. 11 is a diagram for explaining Example 3-1; FIG. 10 is a diagram for explaining Example 3-2; 2 is a diagram illustrating an example of a functional configuration of a user device 10; FIG. 2 is a diagram showing an example of a functional configuration of a base station 20; FIG. 2 is a diagram showing an example of hardware configurations of the user equipment 10 and the base station 20. FIG.

An embodiment (this embodiment) of the present invention will be described below with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.

Existing technology can be used as appropriate for the operation of the wireless communication system of the present embodiment. However, the existing technology is, for example, existing LTE, but is not limited to existing LTE. In addition, “LTE” used in this specification has a broad meaning including LTE-Advanced and LTE-Advanced and subsequent systems (eg, 5G) unless otherwise specified.

In addition, in the embodiments described below, random access used in existing LTE, RA preamble, RAR, messages 1 to 4, RAR window, SIB, MIB, PBCH, DCI, MAC, RRC, other terms are used for convenience of description and similar signals, functions, etc. may be referred to by other names.

Also, in the present embodiment, a random access procedure based on the random access procedure stipulated in LTE is taken as an example. However, the application of the present invention is not limited to the random access procedure. The present invention is also applicable to communication procedures other than random access procedures.

Also, selecting the broadcast information/SS linked to the beam may be considered synonymous with selecting the beam.

In the following description, Examples 1 to 3 will be described, but before describing Examples 1 to 3, a basic example as a technology underlying the Examples 1 to 3 will be described. Examples 1-3 are described as improvements to the basic example.

(basic example)
<Overall system configuration>
FIG. 1 shows a block diagram of a radio communication system according to this embodiment. The radio communication system according to the present embodiment includes user equipment 10 and base station 20, as shown in FIG. Although FIG. 1 shows one user equipment 10 and one base station 20, this is an example and there may be more than one of each.

The user device 10 is a communication device having a wireless communication function such as a smart phone, a mobile phone, a tablet, a wearable terminal, or a communication module for M2M (Machine-to-Machine). Use various communication services provided by The base station 20 is a communication device that provides one or more cells and wirelessly communicates with the user equipment 10 . Both the user equipment 10 and the base station 20 can perform beamforming to transmit and receive signals.

In the present embodiment, the duplex system may be a TDD (Time Division Duplex) system or an FDD (Frequency Division Duplex) system.

Also, in the following description, transmitting a signal using a transmission beam is synonymous with transmitting a signal multiplied by a precoding vector (precoded with a precoding vector). Similarly, receiving a signal using a receive beam is synonymous with multiplying the received signal by a predetermined weight vector. Also, transmitting a signal using a transmit beam may be expressed as transmitting a signal at a specific antenna port. Similarly, receiving a signal using a receive beam may be referred to as receiving the signal at a particular antenna port. Note that the antenna port refers to a logical antenna port defined by the 3GPP standard. Note that the method of forming the transmission beam and the reception beam is not limited to the above method. For example, in the user equipment 10/base station 20 equipped with multiple antennas, a method of changing the angle of each antenna may be used, or a method of combining a method of using a precoding vector and a method of changing the angle of the antenna may be used. Alternatively, other methods may be used.

In the following description, a beam used for signal transmission from the base station 20 is called a BS transmission beam, a beam used for signal reception by the base station 20 is called a BS reception beam, and a beam used for signal transmission from the user equipment 10 is called a BS reception beam. is called a UE transmission beam, and a beam used by the user equipment 10 for signal reception is called a UE reception beam.

<Regarding the random access procedure>
An example of a random access procedure in this embodiment will be described with reference to FIG. In the present embodiment, as an example, a random access procedure similar to the random access procedure in LTE (Non-Patent Document 1) is executed. However, in transmitting and receiving signals in the random access procedure, the user equipment 10 and the base station 20 apply transmission beams and reception beams, respectively. Note that some signal transmission/reception may be omni transmission/reception.

The base station 20 performs beam sweeping, and transmits basic broadcast information and a synchronization signal (SS: synchronization signal, hereinafter referred to as SS) for each BS transmission beam at each predetermined period (step S101). The transmission periods of the basic broadcast information and the synchronization signal may be the same or different. In addition, SIBs (System Information Blocks), which will be described later, are also transmitted at predetermined intervals for each BS transmission beam. The SIB may be referred to as "system information". In the basic example, the transmission period of the SIB is longer than the transmission period of the basic broadcast information and the synchronization signal, and the size of the SIB is larger than the sizes of both the basic broadcast information and the synchronization signal.

An image of the BS transmission beam is shown in FIG. In the example of FIG. 3, three BS transmit beams A, B, and C are shown. Basic broadcast information, SS, SIB, etc. are transmitted in each of the three BS transmit beams. In beam sweeping, for example, the BS transmission beam is switched every time (eg every symbol).

Basic broadcast information is, for example, basic system information (equivalent to MIB in LTE) transmitted on PBCH. SS has, for example, two types of signals (code sequences) of P-SS and S-SS. P-SS is a signal intended for symbol timing synchronization, for example, and S-SS is a signal intended for radio frame synchronization, for example.

A user equipment 10 can identify a BS transmission beam by receiving basic broadcast information or SS or "basic broadcast information and SS" by the BS transmission beam. Identifying a BS transmission beam means, for example, detecting an identifier (ID) of the BS transmission beam. The ID of the BS transmit beam may be the antenna port number. For example, the BS transmission beam ID may be included in the basic broadcast information or may be included in the SS. In addition, the ID of the BS transmission beam is associated with the resource (time and/or frequency resource) for transmitting the basic broadcast information or the SS, and the user equipment 10 receives the basic broadcast information or the SS. BS transmit beams may be identified.

A block containing either P-SS, S-SS, or broadcast information may be referred to as an SS-block. The fact that the user equipment 10 has received the SS block transmitted from the base station 20 (the content of the SS block has been grasped) means that the BS transmission beam associated with the SS block has been identified. , may be In this case, for example, the user equipment 10 identifies the ID of the BS transmission beam from the content of the received SS block or the resource from which the SS block was received.

When the SS block resource and the BS transmission beam are associated, the “BS transmission beam ID” identified by the user equipment 10 is the ID assigned for the BS transmission beam (this will be referred to as “beam ID”). No need. For example, the time position (eg, symbol index) of the above SS block is associated with the BS transmission beam and with the RACH resource subset, which is the resource used to transmit the RA preamble. In this case, this time position (eg symbol index) can be considered as the 'ID of the BS transmit beam'. In this case, the user equipment 10 only needs to recognize the time position (eg symbol index) of the SS block. Also, in this case, for example, the beam ID may be included in the basic broadcast information.

In addition, when the SS block resource and the BS transmission beam are associated, for example, when there are BS transmission beam A and BS transmission beam B, the same BS transmission beam is used with symbol A every time in a certain time unit period. A is used and the same BS transmit beam B in symbol B is used.

Further, when the resource of the SS block and the BS transmission beam are not associated, for example, the base station 20 transmits the basic broadcast information including the beam ID to the user equipment 10, and the user equipment 10 receives the basic The BS transmission beam is identified by reading the beam ID transmitted by the broadcast information.

The technology in this embodiment is applicable to both of the above two patterns. In step S102 in FIG. 2 , the user equipment 10 receives the basic broadcast information and/or the resources corresponding to the BS transmission beams of the SS (which is denoted as “basic broadcast information/SS”) received in step S101 (referred to as RACH resource subset) is used to transmit RA preamble (Message1).

Upon detecting the RA preamble, the base station 20 transmits the RA response (RAR, Message2) to the user equipment 10 (step S103). Upon receiving the RA response, the user equipment 10 transmits Message3 including predetermined information to the base station 20 (step S104). Message3 is, for example, RRC connection request.

The base station 20 that received Message3 transmits Message4 (eg, RRC connection setup) to the user equipment 10 . When the user device 10 confirms that the predetermined information is included in Message4, the user device 10 recognizes that Message4 is Message4 corresponding to Message3 and addressed to itself, and completes the random access procedure. On the other hand, if the user device 10 fails to confirm the predetermined information in Message 4, it is regarded as failure of random access, and the procedure is executed again from the transmission of the RA preamble.

<How to send RA preamble>
An example of the RA preamble transmission method in step S102 above will be described in more detail.

In the present embodiment, the user equipment 10 selects the received basic broadcast information/SS from a plurality of basic broadcast information/SS transmitted from the base station 20 by applying beam sweeping. This is equivalent to selecting the BS transmit beam that transmits the basic broadcast information/SS that could be received. Here, "received" means, for example, that the signal was received with good reception quality, but is not limited to this. Also, the reception quality may be the reception quality of the basic broadcast information/SS itself, or the reception quality of the reference signal made receivable by the basic broadcast information/SS.

In the present embodiment, BS transmission beams from base station 20 are associated with RACH resource subsets, which are resources used for transmitting RA preambles from user equipment 10 . User equipment 10 transmits the RA preamble using the RACH resource subset corresponding to the selected BS transmission beam.

As an example, FIG. 4 shows A, B, and C as RACH resource subsets on the user equipment 10 side. The RACH resource subsets A, B, C correspond respectively to the BS transmit beams A, B, C as shown in FIG. 3, for example. Note that FIG. 4 associates each BS transmission beam with a plurality of RACH resource subsets divided in the time direction, but this is only an example. A plurality of RACH resource subsets may be divided in the frequency direction to correspond to each BS transmission beam, or a plurality of RACH resource subsets may be divided in time/frequency units to correspond to each BS transmission beam. may be attached.

The example of FIG. 4 shows a case where the user equipment 10 is able to receive the basic broadcast information/SS transmitted by the BS transmission beam B, and the user equipment 10 receives the RACH resource subset B corresponding to the BS transmission beam B. to transmit the RA preamble.

The base station 20 can determine the basic broadcast information/SS (BS transmission beam) received at the user equipment 10 based on the resources of the RA preamble received from the user equipment 10 . In the example of FIG. 4, the base station 20 receives the RA preamble using the RACH resource subset B, so the BS transmission beam B corresponding to the RACH resource subset B is an appropriate BS transmission beam that can be received by the user equipment 10. It can be determined that there is For example, the BS transmit beam B can be used in subsequent signal transmissions to the user equipment 10 . In FIG. 4, the beams indicated by E, F, and G on the base station 20 side indicate BS reception beams. shows what is going on.

FIG. 4 also shows the RAR window. In the present embodiment, as in the existing LTE, if the user equipment 10 that has transmitted the RA preamble does not receive the RA response within the predetermined time indicated by the RAR window, it is determined that random access has failed. However, this is only an example, and the RA response reception success/failure determination process may be performed differently from the existing LTE.

The example of FIG. 4 shows the case where the user equipment 10 could receive the basic broadcast information/SS with one BS transmission beam. Alternatively, in the example of FIG. 4, the user equipment 10 can receive the basic broadcast information/SS on multiple BS transmission beams, and among the multiple BS transmission beams, the basic broadcast information/SS can be best received (eg, It shows the case of selecting one BS transmission beam (with the best reception quality).

When the user equipment 10 can receive the broadcast information/SS with multiple BS transmission beams, the user equipment 10 transmits the RA preamble using multiple RACH resource subsets corresponding to each of the multiple BS transmission beams. may be Diversity benefits are obtained by transmitting RA preambles using multiple RACH resource subsets.

For example, when there are multiple BS transmission beams that have received the basic broadcast information/SS (or reference signal) with equally good reception quality, the user equipment 10 selects these multiple BS transmission beams, A RA preamble is transmitted on each of multiple RACH resource subsets corresponding to multiple BS transmission beams. This may allow the base station 20 to detect the truly optimal BS transmission beam. Also, since it is conceivable that UE transmission beams and/or BS reception beams are different between a plurality of RACH resource subsets, the base station 20 may be able to receive RA preambles on the optimum beams.

FIG. 5 shows, as an example, a case where the user equipment 10 transmits RA preambles using RACH resource subsets B and C corresponding to BS transmission beams B and C. In FIG. Note that when RA preambles are transmitted in each of a plurality of RACH resource subsets, the content (sequence) of the RA preambles may be the same or different between the plurality of RACH resource subsets.

<Regarding the method of notifying the RACH resource subset>
In the present embodiment, base station 20 transmits information indicating RACH resource subsets corresponding to BS transmission beams to user equipment 10 . Based on this information, the user equipment 10 can know the RACH resource subset corresponding to the BS transmission beam of the received basic broadcast information/SS. As an example, when the user equipment 10 receives information indicating the RACH resource subset A from the base station 20 as the RACH resource subset corresponding to the BS transmission beam A, the user equipment 10 selects the BS transmission beam A. When transmitting the RA preamble, the user equipment 10 uses the RACH resource subset A to transmit the RA preamble.

The "information indicating the RACH resource subset" notified from the base station 20 to the user equipment 10 may be information indicating the time/frequency resource of the RACH resource subset (eg, resource index), or the time resource of the RACH resource subset. It may be information indicating (time position) or other information.

In a basic example, the above information is signaled for each BS transmission beam using the SIBs transmitted by the BS transmission beams. That is, in this case, the information of the RACH resource subset included in the SIB includes only the information of the RACH resource subset corresponding to the BS transmission beam associated with the SIB.

After receiving the basic broadcast information/SS of a certain BS transmission beam (hereinafter referred to as BS transmission beam A), the user equipment 10 receives the SIB transmitted by BS transmission beam A (SIB corresponding to BS transmission beam A). By reading the SIB, information on the RACH resource subset A corresponding to the BS transmission beam A is obtained, and the RACH resource subset A is used to transmit the RA preamble.

As described with reference to FIG. 5, when the user equipment 10 sends RA preambles using a plurality of RACH resource subsets, if the above-described RACH resource subset notification method (referred to as an individual notification method) is used, , the user equipment 10 needs to receive the SIB for each of the multiple BS transmission beams corresponding to the received basic broadcast/SS, and read the RACH resource subset information from the SIB. However, when such processing is performed, the processing load on the user equipment 10 increases, and there is a possibility that a delay will occur in the transmission of the RA preamble depending on the SIB transmission cycle. A technique for solving this problem will be described below as a first embodiment. Moreover, after Example 1, Example 2 and 3 are also demonstrated.

(Example 1)
Example 1 includes Example 1-1, Example 1-2, and Example 1-3, each of which will be described below. In addition, in the following description of Examples 1-1 to 1-3, improved portions (that is, modified portions) of the techniques of the basic examples described so far are described. Therefore, the basic example applies unless otherwise specified.

Moreover, Examples 1-1, 1-2, and 1-3 may be carried out individually or in combination as appropriate. For example, Examples 1-1 and 1-2 may be combined, Examples 1-1 and 1-3 may be combined, Examples 1-2 and 1-3 may be combined, Examples 1-1, 1-2 and 1-3 may be combined.

<Example 1-1>
In Example 1-1, the SIBs of each BS transmission beam in a plurality of BS transmission beams include, in addition to the information of the RACH resource subset corresponding to the BS transmission beam of the SIB, BS transmissions other than the BS transmission beam of the SIB It contains the information of the RACH resource subset corresponding to the beam.

For example, the SIB of each BS transmission beam in all BS transmission beams used for beam sweeping indicates the correspondence between BS transmission beams and RACH resource subsets for each of all BS transmission beams used in beam sweeping. Correspondence information may be included.

FIG. 6 shows an example of correspondence information when BS transmission beams A, B, and C are used for beam sweeping. In this example, as shown in FIG. 6, in the SIB of BS transmission beam A, BS transmission beam A and RACH resource subset A correspond, BS transmission beam B and RACH resource subset B correspond, and BS transmission beam Information indicating that C and RACH resource subset C correspond is included. Further, as shown in FIG. 6, the SIB of BS transmission beam B and the SIB of BS transmission beam C each contain information similar to the information contained in the SIB of BS transmission beam A.

Also, for example, the SIB of each BS transmission beam in all the BS transmission beams used for beam sweeping is the BS transmission for some of the BS transmission beams out of all the BS transmission beams used for beam sweeping Correspondence information indicating correspondence between beams and RACH resource subsets may be included. Some BS transmit beams are, for example, a BS transmit beam and one or more BS transmit beams adjacent to the BS transmit beam with respect to the SIB of the BS transmit beam.

FIG. 7 shows an example in which the SIB contains correspondence information indicating correspondence between BS transmission beams and RACH resource subsets for some BS transmission beams. In this example, the BS transmit beams used for beam sweeping are BS transmit beams A, B, C, D, where A is adjacent to B and D, B is adjacent to A and C, and C is adjacent to D. B is adjacent and D is adjacent to A and C. In this case, the SIB of BS transmission beam A includes corresponding information about BS transmission beam A, BS transmission beam B, and BS transmission beam D, as shown in FIG. Similarly, the SIBs of the BS transmission beams B to D also contain corresponding information based on the adjacency relationship.

In addition, in this embodiment, it is assumed that SIBs linked to a certain BS transmission beam are transmitted by the BS transmission beam. However, SIBs linked to a certain BS transmission beam may be transmitted in BS transmission beams other than the BS transmission beam, or in omni.

For example, when BS transmission beams A to D are used for beam sweeping, and the SIB shown in FIG. It is assumed that BS transmission beam B receives basic broadcast information/SS and BS transmission beam A and BS transmission beam B are selected. In this case, for example, the user equipment 10 acquires only the SIB of the BS transmission beam A out of the SIB of the BS transmission beam A and the SIB of the BS transmission beam B, and the RACH resource subset A corresponding to the BS transmission beam A and the information of RACH resource subset B corresponding to BS transmit beam B can be obtained. The user equipment 10 transmits the RA preamble using the RACH resource subset A and also transmits the RA preamble using the RACH resource subset B.

Also, in the case of FIG. 7, for example, when the user equipment 10 selects the BS transmission beams A to D, the user equipment 10 acquires the SIB of the BS transmission beam A and the SIB of the BS transmission beam B, for example. to obtain the information of the RACH resource subset corresponding to each BS transmission beam.

Since the number of SIBs to be acquired in the user device 10 can be reduced by the embodiment 1-1, the processing load can be reduced and the processing can be performed quickly.

<Example 1-2>
In Example 1-2, broadcast information having a smaller size and a shorter transmission period than SIBs is provided, and information of RACH resource subsets corresponding to BS transmission beams for transmitting the broadcast information is included in the broadcast information.

The transmission period of the broadcast information having a transmission period shorter than that of the SIB may be the same as the transmission period of the SS, for example. FIG. 8 shows an image of timing for transmitting (receiving for the user device 10) broadcast information in this case. A in FIG. 8 indicates the SS transmission timing, and B in FIG. 8 indicates the broadcast information transmission timing.

Also, the basic broadcast information of the BS transmission beam may include information of the RACH resource subset corresponding to the BS transmission beam. That is, the above broadcast information may be the basic broadcast information described in the basic example. The size of the basic broadcast information is smaller than the size of the SIB, and the transmission cycle of the basic broadcast information is shorter than the SIB transmission cycle.

The base station 20 transmits the above broadcast information or basic broadcast information for each BS transmission beam. For example, when BS transmission beams A to D are used for beam sweeping, the user equipment 10 receives basic broadcast information/SS in each of BS transmission beam A and BS transmission beam B, and BS transmission beam A and BS Assume that transmit beam B is selected. In this case, for example, the user equipment 10 acquires information about the RACH resource subset A corresponding to the BS transmission beam A from the broadcast information or the basic broadcast information of the BS transmission beam A, and obtains the information of the BS transmission beam B or the basic broadcast information. From the information, the information of RACH resource subset B corresponding to BS transmission beam B is obtained. Then, the user equipment 10 transmits the RA preamble using the RACH resource subset A and also transmits the RA preamble using the RACH resource subset B.

In the embodiment 1-2, when acquiring the information of the RACH resource subset, the user equipment 10 reads broadcast information or basic broadcast information smaller in size than the SIB, so the processing load can be reduced compared to the basic example. . Also, since the user equipment 10 reads broadcast information or basic broadcast information with a shorter transmission cycle than the SIB, it is possible to reduce delay compared to the basic example.

<Example 1-3>
In Examples 1-3, as in the basic example, the SIB of a BS transmission beam contains only the information of the RACH resource subset corresponding to that BS transmission beam. However, in Examples 1-3, the relative relationship of the basic broadcast information/SS resource positions between the BS transmission beams is associated with the relative relationship of the RACH resource subset resource positions between the BS transmission beams. Information indicating this association (correspondence relationship) may be information preset in the user equipment 10 and the base station 20, or determined by the base station 20 and sent to the user equipment 10 by higher layer signaling or the like. It may be information to be set.

For example, the value obtained by subtracting the value indicating the resource position of the basic broadcast information/SS in the BS transmission beam A from the value indicating the resource position of the basic broadcast information/SS in the BS transmission beam B is Δ (the unit of Δ may be time. , frequency, time/frequency index, or other), the RACH resource subset corresponding to BS transmission beam A is determined from the value indicating the resource position of the RACH resource subset corresponding to BS transmission beam B. The value obtained by subtracting the value indicating the resource location of is also Δ. FIG. 9 shows an example where Δ is three. That is, the correspondence relationship between the relative relationship between A and B shown in FIG. 9A and the relative relationship between C and D shown in FIG. is defined.

Note that the correspondence relationship may be, for example, information defined for each set of BS transmission beams (two BS transmission beams) in a plurality of BS transmission beams used in beam sweeping, or other information. may An example of operation when the correspondence (correspondence using Δ) as described above is defined is as follows.

For example, when BS transmission beams A to D are used for beam sweeping, the user equipment 10 receives basic broadcast information/SS in each of BS transmission beam A, BS transmission beam B, and BS transmission beam C, Assume that the BS transmission beam C is selected from the BS transmission beam A and the BS transmission beam B.

The user equipment 10 receives, for example, the SIB of one BS transmission beam (here, BS transmission beam A as an example) out of BS transmission beam A, BS transmission beam B, and BS transmission beam C, and Read the information of RACH resource subset A corresponding to BS transmit beam A from . Then, the user equipment 10 determines the correspondence relationship between the relative relationship between the resource positions of the basic broadcast information/SS between the BS transmission beams A to C and the relative relationship between the resource positions of the RACH resource subsets between the BS transmission beams A to C. Based on this, RACH resource subset B corresponding to BS transmission beam B and RACH resource subset C corresponding to BS transmission beam C are identified.

Specifically, for example, the value obtained by subtracting the value indicating the resource location of the basic broadcast information/SS in the BS transmission beam A from the value indicating the resource location of the basic broadcast information/SS in the BS transmission beam B is Δ1, and the BS The value obtained by subtracting the value indicating the resource position of the basic broadcast information/SS in the BS transmission beam A from the value indicating the resource position of the basic broadcast information/SS in the transmission beam C is Δ2, and the RACH resource corresponding to the BS transmission beam A Let P be the resource location of subset A. In this case, for example, the user equipment 10 can determine the resource position of RACH resource subset B corresponding to BS transmission beam B as P+Δ1, and the resource position of RACH resource subset C corresponding to BS transmission beam C as P+Δ2. be able to.

The embodiment 1-3 reduces the processing load on the user device 10 and speeds up the processing.

(Example 2)
Next, Example 2 will be described. The second embodiment is based on the first embodiment. However, the second embodiment may be based on the basic example instead of the first embodiment. Embodiment 2 relates to a transmission procedure in the case where the user equipment 10 transmits an RA preamble using a plurality of RACH resource subsets corresponding to a plurality of BS transmission beams associated with a plurality of received basic broadcast information/SS. Explain technology.

An example 1 of the RA preamble transmission method according to the second embodiment will be described with reference to FIG. The example shown in FIG. 10 shows an example in which RACH resource subset B and RACH resource subset C are selected as multiple RACH resource subsets for transmitting RA preambles. This premise is the same for example 2 (FIG. 11) described later.

As shown in FIG. 10(a), in Example 1, first, the user apparatus 10 transmits an initial RA preamble using one RACH resource subset B among a plurality of RACH resource subsets. In this example, for example, the user equipment 10 cannot receive the RAR within the RAR window, so it decides to retransmit the RA preamble.

As shown in FIG. 10(b), the user apparatus 10 performs RACH resource switching at the time of retransmission, and performs retransmission using another RACH resource subset C. FIG. In example 1, the random access procedure can take a long time depending on the number of received broadcast information/SSs (the number of received BS transmit beams).

An example 2 of the RA preamble transmission method according to the second embodiment will be described with reference to FIG.

As shown in FIG. 11 , in Example 2, the user apparatus 10 uses RACH resource subsets B and C corresponding to a plurality of BS transmission beams, respectively, without waiting for the RAR window (before retransmission), and at the same time performing the RA preamble. to send. Also, of the multiple RACH resource subsets selected for transmission of the RA preamble, some (one or more) RACH resource subsets are used simultaneously to transmit the RA preamble, the remaining (one or Multiple) RACH resource subsets may be used for retransmissions. Note that, for example, when the RACH resource subsets B and C are different resources in the time domain, as shown in FIG. 11, the RA preamble can be transmitted using the RACH resource subsets B and C without waiting for the RAR window is not strictly "simultaneous", but in the second embodiment, such a case is also called "simultaneous". In other words, the case of transmitting using multiple RACH resource subsets without waiting for the RAR window is called "simultaneous".

In Example 2, the base station 20 can determine the optimum beam among multiple BS transmission beams at an early timing without waiting for retransmission of the RA preamble. However, in example 2, if multiple user equipments freely select and transmit RA preambles using multiple RACH resource subsets, there is a possibility that many collisions will occur.

Therefore, in the second embodiment, when RA preambles are transmitted using a plurality of RACH resource subsets as in example 2, the number of types of RA preamble sequences that can be used (the number of RA preambles that can be used) is limited. limit the group of RA preamble sequences that can be used (group of RA preambles that can be used), or limit the number of RACH resource subsets that can be used for simultaneous transmission of RA preambles.

Here, the above "number of RA preambles that can be used", "group of RA preambles that can be used", and "number of RACH resource subsets that can be used" are referred to as "RA preamble transmission method".

As shown in FIG. 12, the RA preamble transmission method is notified from the base station 20 to the user equipment 10 by, for example, basic broadcast information/SS, system information, DCI, MAC signal, or RRC signaling (step S201). . The user equipment 10 transmits the RA preamble by the transmission method according to the notification from the base station 20 (step S202).

Note that instead of notifying the user equipment 10 of the RA preamble transmission method from the base station 20, the user equipment 10 and the base station 20 may each set the RA preamble transmission method in advance.

When limiting the number of RA preambles that can be used, the number of RA preambles is specified as the RA preamble transmission method. As an example, assume that the user equipment 10 has detected three BS transmission beams and learned RACH resource subsets A, B, and C for RA preamble transmission. In this case, for example, when 2 is specified as the number of RA preambles, the user equipment 10 transmits the same RA preamble in each of the two RACH resource subsets among the RACH resource subsets A, B, and C. , transmit another RA preamble on the remaining one RACH resource subset.

When limiting the group of RA preambles that can be used, the group of RA preambles is designated as the RA preamble transmission method. One or more groups may be specified.

For example, there are N RA preambles as a whole (N is an integer of 2 or more), and N are group 1 (N1 RA preambles), group 2 (N2 RA preambles), group 3 (N3 RA preamble). N1+N2+N3=N.

As an example, assume that the user equipment 10 has detected three BS transmission beams and learned RACH resource subsets A, B, and C for RA preamble transmission. In this case, for example, if Group 1 is designated as a group of RA preambles, user equipment 10 transmits RA preambles selected from Group 1 in each of RACH resource subsets A, B, and C. Further, for example, when Group 1 and Group 2 are specified as groups of RA preambles, user equipment 10 selects RA preambles from Group 1 or Group 2 in each of RACH resource subsets A, B, and C. to send.

As described above, by limiting the number or groups of RA preambles that can be used by individual user equipments, it is possible to reduce the collision probability of RA preambles between user equipments.

When limiting the number of RACH resource subsets that can be used, the number of RACH resource subsets is specified as a method of transmitting RA preambles. As an example, assume that the user equipment 10 has detected three BS transmission beams and learned RACH resource subsets A, B, and C for RA preamble transmission. In this case, for example, when 2 is specified as the number of RACH resource subsets, the user equipment 10 uses two RACH resource subsets out of RACH resource subsets A, B, and C to transmit RA preambles. do. When 2 is specified as the number of RACH resource subsets, in the step of identifying multiple RACH resource subsets for RA preamble transmission, only two RACH resource subsets may be identified.

Also, in the second embodiment, switching between example 1 described with reference to FIG. 10 and example 2 described with reference to FIG. When the base station 20 instructs the user equipment 10 to implement Example 1, the number of RACH resource subsets that the user equipment 10 can use simultaneously is limited to one. When the base station 20 instructs the user equipment 10 to implement Example 2, the user equipment 10 can freely select the number of RACH resource subsets and the number of RA preambles. Alternatively, when instructing the user equipment 10 from the base station 20 to implement Example 2, in addition to the instruction, "number of RA preambles that can be used", "group of RA preambles that can be used", or "use The number of possible RACH resource subsets' may be indicated.

Further, in the second embodiment, apart from the restriction notification such as "the number of RA preambles that can be used", "the group of RA preambles that can be used", or "the number of RACH resource subsets that can be used", from the base station 20 to the user equipment 10 , may be instructed by signaling or the like whether simultaneous transmission using multiple RACH resource subsets may be performed, and the base station 20 may instruct the user equipment 10 to retransmit the RA preamble before that. Signaling or the like may be used to indicate whether or not a RACH resource subset different from the RACH resource subset used for transmission of the RA preamble may be used.

By limiting the number of RACH resource subsets that can be used by individual user equipments, as described above, it is easier for the base station 20 to identify the RACH resource subsets. Also, by reducing the number of RACH resource subsets used for simultaneous transmission, the number of RACH resource subsets available for retransmission increases.

(Example 3)
Example 3 assumes that RA preambles are simultaneously transmitted using a plurality of RACH resource subsets, as described in Example 2 (FIG. 11) of Example 2. FIG. However, the number of RA preambles or the limitation of the number of groups/the limitation of the number of RACH resource subsets described in the second embodiment may or may not be applied. Also, in the third embodiment, the method of specifying a plurality of RACH resource subsets in the first embodiment may or may not be applied.

Embodiment 3 will explain an example of a method of transmitting RA responses (RAR) from the base station 20 when simultaneously transmitting one type (one sequence) of RA preambles using a plurality of RACH resource subsets. Example 3 has Example 3-1 and Example 3-2, each of which will be described below.

<Example 3-1>
In Example 3-1, the base station 20 transmits one RAR for each received RACH resource subset. Each RAR includes information indicating which RACH resource subset the RAR corresponds to (eg, RACH resource subset index) and one Msg3 scheduling grant. In addition, the base station 20, instead of explicitly including the above information (information indicating the RACH resource subset and / or Msg3 scheduling grant) in the RAR, user equipment by the time and / or frequency resource position to transmit the RAR 10 may be notified.

A specific example of Example 3-1 will be described with reference to FIG. In step S301, basic broadcast information/SS is transmitted from the base station 20 to the user equipment 10 by beam sweeping. At the user equipment 10, multiple BS transmission beams are selected and multiple RACH resource subsets corresponding to the multiple BS transmission beams are identified. Here, it is assumed that the multiple RACH resource subsets are RACH resource subset A and RACH resource subset B.

In step S302, the user equipment 10 uses RACH resource subset A to transmit the RA preamble, and uses RACH resource subset B to transmit the same RA preamble.

In step S303, the base station 20 transmits RAR-A for the RA preamble received on the RACH resource subset A and RAR-B for the RA preamble received on the RACH resource subset B to the user equipment 10. For example, RAR-A includes information indicating that RA preamble is received by RACH resource subset A and Msg3 scheduling grant, and RAR-B includes RA preamble received by RACH resource subset B and Msg3 scheduling grant. The UL resource specified by Msg3 scheduling grant included in RAR-A is different from the UL resource specified by Msg3 scheduling grant included in RAR-B.

In step S304, the user equipment 10 transmits Msg3 using UL resources specified by the Msg3 scheduling grant included in RAR-A and Msg3 using UL resources specified by the Msg3 scheduling grant included in RAR-B. The base station 20 can identify which RACH resource subset the Msg3 corresponds to based on the resources for receiving these Msg3.

<Example 3-2>
In Example 3-2, the base station 20 includes information on all received RACH resource subsets in one RAR and transmits the one RAR. For example, one RAR contains the indices of all received RACH resource subsets and the corresponding Msg3 scheduling grants.

A specific example of Example 3-2 will be described with reference to FIG. In step S311, basic broadcast information/SS is transmitted from the base station 20 to the user equipment 10 by beam sweeping. At the user equipment 10, multiple BS transmission beams are selected and multiple RACH resource subsets corresponding to the multiple BS transmission beams are identified. Here, it is assumed that the multiple RACH resource subsets are RACH resource subset A and RACH resource subset B.

In step S312, the user equipment 10 uses RACH resource subset A to transmit the RA preamble, and uses RACH resource subset B to transmit the same RA preamble.

In step S313, the base station 20 receives information indicating that the RA preamble has been received by the RACH resource subset A (eg, the index of the RACH resource subset A), the Msg3 scheduling grant corresponding to the RACH resource subset A, and the RA preamble is received by RACH resource subset B (eg, index of RACH resource subset B) and Msg3 scheduling grant corresponding to RACH resource subset B.

In step S314, the user equipment 10 transmits Msg3 with UL resources specified by the Msg3 scheduling grant corresponding to RACH resource subset A and Msg3 with UL resources specified by the Msg3 scheduling grant corresponding to RACH resource subset B. do.

Note that the base station 20 may utilize the time and/or frequency resource positions of the RAR to be transmitted, and may convey the information to be included in the RAR as a relative positional relationship without explicitly including it in the RAR.

For example, the RAR time and/or frequency resource position and the UL resource position specified in the Msg3 scheduling grant are associated in advance, and the user equipment 10 and the base station 20 have information on the correspondence (correspondence information 1 and ). Further, the relative relationship of resource positions between a plurality of RACH resource subsets and the relative relationship of UL resource positions between a plurality of Msg3 scheduling grants corresponding to the plurality of RACH resource subsets are associated in advance, and the user equipment 10 and Assume that the base station 20 also holds information on the correspondence (referred to as correspondence information 2).

Here, for example, when the base station 20 receives the RA preamble in the RACH resource subset A and the RACH resource subset B, the base station 20 stores the index of the RACH resource subset A and the index of the RACH resource subset B in the RAR. including, the RAR is transmitted on (DL) resources corresponding to UL resources corresponding to RACH resource subset A (resources for transmitting Msg3). The user equipment 10 grasps the UL resource corresponding to the RACH resource subset A based on the correspondence information 1 and the resource that received the RAR. Also, the user equipment 10 grasps the UL resources corresponding to the RACH resource subset B based on the correspondence information 2 . As an example, when the RACH resource subsets are separated by 3, when using the correspondence relationship that the UL resources that transmit Msg3 are also separated by 3, the user equipment 10, based on the correspondence information 2, the RACH The UL resource for transmitting Msg3 corresponding to resource subset A plus 3 (or subtracting 3) from the UL resource for transmitting Msg3 corresponding to RACH resource subset B is determined as the UL resource for transmitting Msg3 corresponding to RACH resource subset B.

As shown in Examples 3-1 and 3-2 above, in Example 3, when the user equipment 10 receives a plurality of RARs (or, as in Example 3-2, a plurality of RARs ), a plurality of identifiable Msg3 can be sent. With such processing, for example, when the user equipment 10 transmits one RA preamble using multiple RACH resource subsets, even if other user equipment uses the same RA preamble as the RA preamble, the user equipment If there is at least one different RACH resource subset between UE 10 and the other user equipment, collisions can be avoided. That is, it is possible to improve the success probability of the random access procedure.

(Device configuration)
Next, functional configuration examples of the user equipment 10 and the base station 20 that execute the processing operations described above will be described. User equipment 10 and base station 20 each include functionality to implement at least Examples 1-3. However, each of the user equipment 10 and the base station 20 may have only some of the functions in the first to third embodiments. Also, the user equipment 10 and the base station 20 may have a function capable of executing the processing described in the basic example.

<User device>
FIG. 15 is a diagram showing an example of the functional configuration of the user device 10. As shown in FIG. As shown in FIG. 15 , the user equipment 10 has a signal transmission section 101 , a signal reception section 102 , a setting information management section 103 and an RA control section 104 . The functional configuration shown in FIG. 15 is merely an example. As long as the operation according to the present embodiment can be executed, the functional division and the name of the functional unit may be arbitrary.

The signal transmission unit 101 creates a transmission signal from transmission data and wirelessly transmits the transmission signal. The signal receiving unit 102 wirelessly receives various signals and acquires a higher layer signal from the received physical layer signal. The signal transmitting unit 101 is configured to perform beamforming on the transmitting side, and the signal receiving unit 102 is configured to perform beamforming on the receiving side. Note that the signal transmission unit 101 may be called a transmitter. The signal receiving section 102 may be called a receiver.

The setting information management unit 103 stores various setting information received from the base station 20 by the signal receiving unit 102 . The content of the setting information is, for example, the correspondence information described above. The setting information management unit 103 also stores preconfigured setting information in the user device 10 .

The RA control unit 104 performs random access procedure processing in the user equipment 10 described in the first to third embodiments. The functional unit related to signal transmission in RA control unit 104 may be included in signal transmitting unit 101 , and the functional unit related to signal reception in RA control unit 104 may be included in signal receiving unit 102 .

Further, for example, the signal receiving unit 102 is configured to receive a plurality of predetermined signals transmitted by a plurality of beams from the base station 20, and the signal transmitting unit 101 receives a plurality of predetermined signals corresponding to the plurality of beams. configured to transmit a preamble using a resource, further configured to receive system information including information of the plurality of resources corresponding to the plurality of beams from the base station 20, the signal receiving unit 102; A signal transmitting unit 101 is configured to obtain information of the plurality of resources from the system information.

Further, for example, the signal receiving unit 102 is configured to receive a plurality of predetermined signals transmitted by a plurality of beams from the base station 20, and the signal transmitting unit 101 receives a plurality of predetermined signals corresponding to the plurality of beams. configured to transmit a preamble using resources, and further, the signal transmission unit 101 corresponds to the plurality of beams based on the resource position relationship between the plurality of predetermined signals received by the signal reception unit 102 determining the plurality of resources to be used.

Further, for example, the signal receiving unit 102 receives a notification indicating the number of preambles, the group of preambles, or the number of resources in the plurality of resources from the base station 20, and the signal transmitting unit 101 follows the notification. , to transmit the preamble.

Further, for example, the signal receiving unit 102 receives information designating a plurality of uplink transmission resources corresponding to the plurality of resources, and the signal transmission unit 101 transmits a message using each of the plurality of uplink transmission resources. Send to base station 20 .

<Base station 20>
FIG. 16 is a diagram showing an example of the functional configuration of the base station 20. As shown in FIG. As shown in FIG. 16 , the base station 20 has a signal transmission section 201 , a signal reception section 202 , a setting information management section 203 and an RA control section 204 . The functional configuration shown in FIG. 16 is merely an example. As long as the operation according to the present embodiment can be executed, the functional division and the name of the functional unit may be arbitrary.

The signal transmission unit 201 includes a function of generating a signal to be transmitted to the user device 10 side and wirelessly transmitting the signal. The signal receiving unit 202 includes a function of receiving various signals transmitted from the user equipment 10 and acquiring, for example, higher layer information from the received signals. The signal transmitting unit 201 is configured to perform beamforming on the transmitting side, and the signal receiving unit 202 is configured to perform beamforming on the receiving side. Note that the signal transmission unit 201 may be called a transmitter. The signal receiving section 202 may be called a receiver.

The setting information management unit 203 stores various setting information to be transmitted to the user device 10 . This is the content of the setting information, for example, the correspondence information described above. The configuration information management unit 203 also stores configuration information preconfigured in the base station 20 .

The RA control unit 204 executes the processing of the random access procedure in the base station 20 described in the first to third embodiments. Note that the functional unit related to signal transmission in RA control unit 204 may be included in signal transmitting unit 201 and the functional unit related to signal reception in RA control unit 204 may be included in signal receiving unit 202 .

Further, for example, the signal transmission unit 201 is configured to transmit a plurality of predetermined signals using a plurality of beams, and the signal reception unit 202 receives the signal from the user equipment 10 using a plurality of resources corresponding to the plurality of beams. The signal transmitting unit 201 is configured to receive the transmitted preamble, and the signal transmission unit 201 is configured to transmit system information including information indicating the plurality of resources used for transmission of the preamble in the user equipment 10. be done. The signal transmission unit 201 also includes a function of transmitting RAR by the method described in the third embodiment. Also, the signal transmission unit 201 may include a function of including the beam ID in the basic system information and transmitting the same.

<Hardware configuration>
The block diagrams (FIGS. 15 and 16) used to describe the above embodiments show blocks in units of functions. These functional blocks (components) are implemented by any combination of hardware and/or software. Further, means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one device in which multiple elements are physically and/or logically combined, or may be realized by two or more devices that are physically and/or logically separated. and/or may be indirectly (eg, wired and/or wireless) connected and implemented by these multiple devices.

Also, for example, both the user equipment 10 and the base station 20 according to the embodiment of the present invention may function as a computer that performs processing according to the present embodiment. FIG. 17 is a diagram showing an example of the hardware configuration of user equipment 10 and base station 20 according to the present embodiment. Each of the user device 10 and the base station 20 described above may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. good.

Note that in the following description, the term "apparatus" can be read as a circuit, device, unit, or the like. The hardware configuration of the user device 10 and the base station 20 may be configured to include one or more of each device indicated by 1001 to 1006 shown in the figure, or may be configured without some devices. may

Each function in the user device 10 and the base station 20 is performed by loading predetermined software (programs) on hardware such as the processor 1001 and the memory 1002, the processor 1001 performs calculations, communication by the communication device 1004, memory 1002 and by controlling reading and/or writing of data in the storage 1003 .

The processor 1001, for example, operates an operating system to control the entire computer. The processor 1001 may be configured with a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, registers, and the like.

The processor 1001 also reads programs (program codes), software modules, or data from the storage 1003 and/or the communication device 1004 to the memory 1002, and executes various processes according to them. As the program, a program that causes a computer to execute at least part of the operations described in the above embodiments is used. For example, the signal transmission unit 101, the signal reception unit 102, the setting information management unit 103, and the RA control unit 104 of the user device 10 shown in FIG. good too. Further, for example, the signal transmission unit 201, the signal reception unit 202, the setting information management unit 203, and the RA control unit 204 of the base station 20 shown in FIG. may be realized by Although it has been described that the above-described various processes are executed by one processor 1001, they may be executed by two or more processors 1001 simultaneously or sequentially. Processor 1001 may be implemented with one or more chips. Note that the program may be transmitted from a network via an electric communication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one of, for example, ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), and the like. may be The memory 1002 may also be called a register, cache, main memory (main storage device), or the like. The memory 1002 can store executable programs (program code), software modules, etc. to perform processing according to one embodiment of the present invention.

The storage 1003 is a computer-readable recording medium, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (for example, a compact disk, a digital versatile disk, a Blu-ray disk), smart card, flash memory (eg, card, stick, key drive), floppy disk, magnetic strip, and/or the like. Storage 1003 may also be called an auxiliary storage device. The storage medium described above may be, for example, a database, server, or other suitable medium including memory 1002 and/or storage 1003 .

The communication device 1004 is hardware (transmitting/receiving device) for communicating between computers via a wired and/or wireless network, and is also called a network device, network controller, network card, communication module, or the like. For example, the signal transmission unit 101 and the signal reception unit 102 of the user device 10 may be implemented by the communication device 1004 . Also, the signal transmission unit 201 and the signal reception unit 202 of the base station 20 may be realized by the communication device 1004 .

The input device 1005 is an input device (for example, keyboard, mouse, microphone, switch, button, sensor, etc.) that receives input from the outside. The output device 1006 is an output device (eg, display, speaker, LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated (for example, a touch panel).

Devices such as the processor 1001 and the memory 1002 are also connected by a bus 1007 for communicating information. The bus 1007 may be composed of a single bus, or may be composed of different buses between devices.

Further, the user equipment 10 and the base station 20 each include a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gauge). Array), etc. It may be configured including hardware, and part or all of each functional block may be realized by the hardware. For example, processor 1001 may be implemented with at least one of these hardware.

(Summary of embodiment)
As described above, according to the present embodiment, the user equipment in a radio communication system having a base station and a user equipment comprises a plurality of predetermined beams transmitted from the base station using a plurality of beams. a receiver that receives a signal; and a transmitter that transmits a preamble using a plurality of resources corresponding to the plurality of beams, wherein the receiver receives information on the plurality of resources corresponding to the plurality of beams. is received from the base station, and the transmission unit acquires the information of the plurality of resources from the system information.

The above configuration provides a technology that enables appropriate execution of a random access procedure to which beamforming is applied in a radio communication system having a user equipment and a base station.

Further, according to the present embodiment, the user equipment in a radio communication system having a base station and a user equipment receives a plurality of predetermined signals transmitted by a plurality of beams from the base station. and a transmitter that transmits a preamble using a plurality of resources corresponding to the plurality of beams, wherein the transmitter determines the relationship of resource positions between the plurality of predetermined signals received by the receiver. A user equipment is provided for determining the plurality of resources corresponding to the plurality of beams based on.

The above configuration provides a technology that enables appropriate execution of a random access procedure to which beamforming is applied in a radio communication system having a user equipment and a base station.

For example, the receiving unit receives from the base station a notification indicating the number of preambles, the group of preambles, or the number of resources in the plurality of resources, and the transmitting unit transmits preambles according to the notification. do. With this configuration, it is possible to reduce the probability of preamble collision between user devices.

For example, the receiving unit receives information designating a plurality of uplink transmission resources corresponding to the plurality of resources, and the transmission unit transmits a message to the base station using each of the plurality of uplink transmission resources. Send. With this configuration, the user equipment can improve the success probability of the random access procedure.

Further, according to the present embodiment, the base station in a radio communication system having a base station and a user equipment, the transmission unit transmitting a plurality of predetermined signals using a plurality of beams, and a receiving unit that receives a preamble transmitted from the user equipment using a plurality of resources, wherein the transmitting unit receives information indicating the plurality of resources used for preamble transmission in the user equipment. A base station is provided characterized by transmitting system information including:

The above configuration provides a technology that enables appropriate execution of a random access procedure to which beamforming is applied in a radio communication system having a user equipment and a base station.

(Supplement to the embodiment)
Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art can understand various modifications, modifications, alternatives, replacements, and the like. be. Although specific numerical examples have been used to facilitate understanding of the invention, these numerical values are merely examples and any appropriate values may be used unless otherwise specified. The division of items in the above description is not essential to the present invention, and the items described in two or more items may be used in combination as necessary, and the items described in one item may be used in another item. may apply (unless inconsistent) to the matters set forth in Boundaries of functional or processing units in functional block diagrams do not necessarily correspond to boundaries of physical components. The operations of a plurality of functional units may be physically performed by one component, or the operations of one functional unit may be physically performed by a plurality of components. As for the processing procedures described in the embodiments, the processing order may be changed as long as there is no contradiction. Although the user equipment 10 and the base station 20 have been described using functional block diagrams for convenience of explanation of processing, such equipment may be implemented in hardware, software, or a combination thereof. The software operated by the processor possessed by the user equipment 10 according to the embodiment of the present invention and the software operated by the processor possessed by the base station 20 according to the embodiment of the present invention are respectively stored in random access memory (RAM), flash memory, read-only It may be stored in memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

Also, the notification of information is not limited to the aspects/embodiments described herein, and may be performed in other ways. For example, the notification of information includes physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), higher layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling). Gnaring, It may be implemented by broadcast information (MIB (Master Information Block), SIB (System Information Block))), other signals, or a combination thereof. The RRC signaling may also be referred to as an RRC message, such as an RRC Connection Setup message, an RRC Connection Reconfiguration message, and the like.

Each aspect/embodiment described herein includes Long Term Evolution (LTE), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), It may be applied to systems utilizing Bluetooth®, other suitable systems, and/or advanced next generation systems based thereon.

The procedures, sequences, flow charts, etc. of each aspect/embodiment described herein may be interchanged so long as there is no inconsistency. For example, the methods described herein present elements of the various steps in a sample order and are not limited to the specific order presented.

Certain operations referred to herein as being performed by the base station 20 may in some cases be performed by its upper nodes. In a network of one or more network nodes with a base station 20, various operations performed for communication with the user equipment 10 may be performed by the base station 20 and/or other nodes other than the base station 20. Obviously, it can be done by a network node (eg, but not limited to MME or S-GW). Although the case where there is one network node other than the base station 20 is exemplified above, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

Each aspect/embodiment described herein may be used alone, in combination, or switched between implementations.

User equipment 10 may be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, It may also be called a wireless terminal, remote terminal, handset, user agent, mobile client, client or some other suitable term.

Base station 20 may also be referred to by those skilled in the art as a NodeB (NB), an enhanced NodeB (eNB), a Base Station, or some other suitable terminology.

As used herein, the terms "determining" and "determining" may encompass a wide variety of actions. "Judgement", "determining" are, for example, judging, calculating, computing, processing, deriving, investigating, looking up (e.g., table , searching in a database or other data structure), ascertaining what has been "determined" or "determined", and the like. Also, “judgment” and “determination” are used to refer to receiving (e.g., receiving information), transmitting (e.g., transmitting information), input, output, access (Accessing) (for example, accessing data in memory) may include deeming that a "judgment" or "decision" has been made. In addition, "judgment" and "decision" refer to resolving, selecting, choosing, establishing, comparing, etc. as "judgment" and "decision". can contain. In other words, "judgment" and "decision" may include considering that some action is "judgment" and "decision".

As used herein, the phrase "based on" does not mean "based only on," unless expressly specified otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

To the extent that "include," "including," and variations thereof are used in the specification or claims, these terms are synonymous with the term "comprising." are intended to be inclusive. Furthermore, the term "or" as used in this specification or the claims is not intended to be an exclusive OR.

Throughout this disclosure, where articles have been added by translation, e.g., a, an, and the in English, these articles are used unless the context clearly indicates otherwise. It can contain more than one.

Although the present invention has been described in detail above, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments described herein. The present invention can be implemented with modifications and variations without departing from the spirit and scope of the invention defined by the claims. Accordingly, the descriptions herein are for the purpose of illustration and description, and are not intended to have any limiting meaning with respect to the present invention.

This patent application claims priority based on Japanese Patent Application No. 2017-001460 filed on January 6, 2017, and the entire contents of Japanese Patent Application No. 2017-001460 are incorporated into this application. do.

10 User equipment 101 Signal transmission unit 102 Signal reception unit 103 Setting information management unit 104 RA control unit 20 Base station 201 Signal transmission unit 202 Signal reception unit 203 Setting information management unit 204 RA control unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device

Claims (5)

a receiver that receives a plurality of synchronization signal blocks corresponding to a plurality of beams;
a transmitting unit that transmits a preamble using one resource among a plurality of resources corresponding to the plurality of synchronization signal blocks;
A terminal, wherein the receiving unit receives an SIB transmitted on a beam among a plurality of SIBs transmitted on a plurality of beams, and each of the plurality of SIBs includes information on the plurality of resources. The terminal according to claim 1, wherein the transmitting section performs preamble transmission using the second resource when the receiving section fails to successfully receive a random access response to the preamble transmitted using the first resource. a transmitter that transmits a plurality of synchronization signal blocks corresponding to a plurality of beams;
a receiving unit that receives a preamble transmitted from the terminal using one of the plurality of resources corresponding to the plurality of synchronization signal blocks;
The base station, wherein the transmitter transmits a plurality of SIBs on a plurality of beams, each of the plurality of SIBs including information of the plurality of resources. a receiver that receives a plurality of synchronization signal blocks corresponding to a plurality of beams;
a transmitting unit that transmits a preamble using one resource among a plurality of resources corresponding to the plurality of synchronization signal blocks;
The receiving unit receives SIBs transmitted in a beam among a plurality of SIBs transmitted in a plurality of beams, and each of the plurality of SIBs includes information on the plurality of resources. A terminal;
a transmitter that transmits the plurality of synchronization signal blocks corresponding to the plurality of beams;
a receiving unit that receives the preamble transmitted from the terminal using one of the plurality of resources corresponding to the plurality of synchronization signal blocks;
A radio communication system comprising: a base station, wherein the transmitting unit transmits the plurality of SIBs on the plurality of beams, each of the plurality of SIBs including information on the plurality of resources. a receiving step of receiving a plurality of synchronization signal blocks corresponding to a plurality of beams;
a transmitting step of transmitting a preamble using one of a plurality of resources corresponding to the plurality of synchronization signal blocks;
In the receiving step , receiving an SIB transmitted on a beam among a plurality of SIBs transmitted on a plurality of beams, each of the plurality of SIBs including information on the plurality of resources;
Preamble transmission method performed by the terminal.

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